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General Discussion

Posted by Rajeev Sharma
Rajeev Sharma
1,597 Points

__NSDictionaryM stringValue]: unrecognized selector sent to instance

if (self.postData) {

        NSMutableString *post = [NSMutableString string];

                for (NSString* key in self.postData) {
                    if ([post length] != 0) {
                        [post appendString:@"&"];
                    }

                    [post appendString:key];
                    [post appendString:@"="];


                    NSString* encodedValue = (NSString *)[[self.postData objectForKey:key]stringValue];
        //                        encodedValue = [encodedValue stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

                    [post appendString:encodedValue];
                }
        post = [[post stringByReplacingOccurrencesOfString:@"+" withString:@"%2B"]mutableCopy];
         NSLog(@"post string=%@", post);

Please help. I am getting a crash at appendString. self.post is a dictionary here.

2 Answers

Ernest Grzybowski
Ernest Grzybowski
Treehouse Project Reviewer
Ernest Grzybowski
Ernest Grzybowski
Treehouse Project Reviewer

It helps to give us where you encountered the problem. Can you please post which lesson this is from exactly? It's important to know which lesson, because different lessons provide different ways to do the same thing. Thanks

Rajeev Sharma
Rajeev Sharma
1,597 Points
Rajeev Sharma
Rajeev Sharma
1,597 Points

I started my own project. This is not related to any lesson.

I think I figured this out. It was the wrong method that is been called on string within the dictionary for loop. I corrected this by replacing appendString to appendFormat.

Thanks :)